In the design stage of robotic hands, it is not straightforward to quantitatively evaluate the effect of phalanx length ratios on dexterity without defining specific objects or manipulation tasks. Therefore, this study presents a framework for optimizing the phalanx length ratios of a five-finger robotic hand based on potential dexterity within a kinematic structure. The proposed method employs global manipulability, workspace volume, overlap workspace volume, and fingertip sensitivity as evaluation metrics, and identifies optimal design configurations using a weighted objective function under given constraints. The reachable workspace is discretized using a voxel-based representation, and joint motions are discretized at uniform intervals for evaluation. The optimization is performed over design sets for both the thumb and the other fingers, and design combinations that do not generate overlap workspace are excluded. The results show that each phalanx does not contribute equally to the overall dexterity, and the factors influencing each phalanx are identified. In addition, it is observed that the selection of weighting coefficients does not necessarily lead to the direct maximization of individual performance metrics, due to the non-uniform distribution of evaluation measures within the design space. The proposed framework provides a systematic approach to analyze the trade-offs among reachability, dexterity, and controllability, and can serve as a practical guideline for the kinematic design of multi-fingered robotic hands.

翻译：在机器人手的设计阶段，若未定义具体对象或操作任务，直接量化指节长度比对灵巧度的影响并不简单。因此，本研究提出一个框架，基于运动学结构中的势灵巧度，对五指机器人手的指节长度比进行优化。该方法采用全局可操作度、工作空间体积、重叠工作空间体积及指尖灵敏度作为评估指标，并在给定约束条件下通过加权目标函数确定最优设计构型。可达工作空间基于体素表征进行离散化，关节运动按均匀间隔离散化以进行评估。优化针对拇指及其他手指的设计集进行，并排除不产生重叠工作空间的设计组合。结果表明，各指节对整体灵巧度的贡献并不相等，并识别出影响各指节的因素。此外，观察到加权系数的选择并不必然导致单项性能指标的直接最大化，这是由于设计空间中评估指标的非均匀分布所致。该框架提供了一种系统化方法，用于分析可达性、灵巧度与可控性之间的权衡，可作为多指机器人手运动学设计的实用指南。